According to one known embodiment, an electronic device comprises a stack consisting of a first chip bonded onto a second chip with larger dimensions, and an electrical connection wafer onto which the second chip is bonded and which has larger dimensions than this second chip.
Front pads of the first chip are connected to front pads of the second chip by first curved electrical connection wires.
Other front pads of the second chip are connected to front pads of the electrical connection wafer by second curved electrical connection wires.
Commonly, the first chip contains a sensor, for example a microelectromechanical system, generally referred to as MEMS, and the second chip contains electronic circuits for processing the signals coming from the sensor, and the processed signals are transmitted to the printed-circuit board through the electrical connection wafer.
The first and second chips and the first and second electrical connection wires are embedded in an encapsulation block formed on the front of the electrical connection wafer with a view to protecting the electrical connection wires and the sensor, in particular from moisture.
The electronic device is then fixed on a printed-circuit board by means of electrical connection beads or pillars.
Such an electronic device has the drawback of being bulky and of being expensive because of the existence of three stacked elements, the existence of electrical connection wires generally made of gold, and the large number of operations to be carried out in order to perform assembly.
There is a need in the art for an electronic device which has a smaller volume and is simpler to fabricate, so that it can be less expensive.